Color bitmap images are represented as digital data at various stages within image display systems and computing systems. For example, digital images can be stored as files using file formats such as PEG, PNG, and TIFF. These image files can be unpacked and displayed on a display device (e.g., a cathode ray tube (CRT), a liquid crystal display (LCD), or an organic light emitting diode (OLED) display). Color digital images may also be transmitted between components of a system. For example, an image file may be read from memory and composed onto a video frame for display on a display device (e.g., composed with user interface elements) and the composed video frame, which itself is a color digital image, may be supplied to a display device over a link.
These various representations of digital color bitmap images can be compressed in order to reduce memory and bandwidth requirements when stored and when transmitted.
FIG. 1 is a block diagram illustrating a computing and display device 100, such as a desktop or portable computer, a smartphone, or a tablet. Such devices 100 often include or are connected to an image capture device 10. The image capture device 10 may be controlled by a processor 20. When the image capture device 10 is controlled to capture an image, the captured image data may be supplied to the processor 20 which may modify the data before storing the data in storage device 30. The storage device 30 may be, for example, NAND flash memory, dynamic random access memory (DRAM), rotating magnetic media (e.g., a hard disk drive), etc. In some embodiments the processor may be configured to control the display device 40 to display images stored on the storage device 30 or images captured by the image capture device 10. A graphical processing unit (GPU) 50 may be coupled between the processor 20 and the display device 40 using a display link. In addition, the display device 40 may include or be coupled to a data demodulation unit 42 which is configured to receive data over the display link and to convert the data into a form for display on the display device 10. Here, the display device 40 may be a liquid crystal display (LCD) device, an organic light emitting diode (OLED) display device, etc.